Why? You should be dreaming of changing the world or of doing well in life, not of getting a letter of acceptance to a “prestigious” college.
You are not even in high school. The entire focus of your energy should be doing your very best over the next four years. It is way to early to be spending time and energy of making colleges decisions, or even thinking too deeply about college.
As it is, you are setting yourself up to wasting the next four years focused on “How Do I Get Into AN IVY?” In all honesty, it is not very likely that you will attend an Ivy. Only about 13,000 students your age will attend an Ivy league college. Of those 13,000, about 7,000 will be from applicant pools of which you are not a part. At least 100,000 students of your age will by applying for these 7,000 places.
Luckily, there are literally hundreds of amazing colleges out there at which you will succeed and thrive, have a great 4 years, and set yourself up for the your life after college. A life, which, I may add, will be, hopefully, more than 15 times as long as your college years.
If you work hard, do your best in classes, put time and effort in ECs which speak to you and about which you are passionate, you will, in all likelihood, be accepted and attend a great college where you will be able to succeed and thrive. It may be an Ivy, it may be a small liberal arts college, it may be a large state research university or a directional. You may even find that your career goals are best served by going through a community college or trade school route.
Your high school ECs are for your benefit. They are a way for you to discover your interests and passions, to find out more about who you are, and to accomplish something while still in high school.
Thinking about ECs as something to do to help you “be accepted to an Ivy” is almost a sure-fire way to have a set of ECs which is not only unimpressive, but is also not very satisfying for you.
Your aim should be to have high school accomplishments, both academic and extracurricular, of which you will be proud, no matter where you end up for college.
Finally, “Ivy League” is the name of a athletic conference, not a series of similar colleges. Each one of the colleges in the conference is very different from the rest, and they are often more similar to colleges outside of the Ivy League than they are to each other.
If you say that your are dreaming of attending “an Ivy”, that means that your dream is to gain some social status from people knowing that you were accepted, and attend, a prestigious college. The actual attendance is not part of your dream at all.
So stop wasting your time asking about colleges here, and go win at high school.